Advances on Capturing Francium in a Magneto-Optical Trap

Abstract

The strong confinement of atoms in six-dimensional phase space in magneto-optic traps makes them a promising tool for work with radioactives. The absence of Doppler broadening and laser-atom interaction more than one thousand times longer compared to atomic beams provide a very good environment for precision measurements. The long term project is to measure parity non-conservation effects in francium. Francium is attractive because the effects are larger than in the other alkalis and francium is trappable. However it does not have stable isotopes. With the Stony Brook linear accelerator we can produce a variety of neutron deficient isotopes. The neutron rich isotopes can come as daughters of radioactive decay in thorium. Since the production rate of radioactive atoms is not high, any experiment with them requires efficient use of the available sample. We have developed an on-line system to capture radioactive atoms from an accelerator.